Newcastle United have asked supporters to refrain from wearing mock headdresses following the club's takeover by a Saudi-backed consortium.
Some fans wore traditional robes and others headdresses for Sunday's Premier League game with Tottenham, the Magpies' first under their new owners.
The fans' actions are seen as a misguided show of support towards the new owners.
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Newcastle said that while their owners took no offence by the fans' attire, it could be considered stereotypical and culturally offensive.
The Premier League club, who sacked manager Steve Bruce on Wednesday, said in a statement: "Newcastle United is kindly asking supporters to refrain from wearing traditional Arabic clothing or Middle East-inspired head coverings at matches if they would not ordinarily wear such attire.
"A number of supporters have recently attended St James' Park wearing associated head coverings and robes, marking the takeover of the club by the Public Investment Fund (PIF), PCP Capital Partners and RB Sports & Media.
"No-one among the new ownership group was in any way offended by the attire of the fans who chose to celebrate in this way. It was a gesture that was acknowledged as positive and welcoming in its intent.
"However, there remains the possibility that dressing this way is culturally inappropriate and risks causing offence to others.
"All visitors to the club are, as always, encouraged to wear whatever is the norm for their own culture or religion, continuing to reflect the broad and rich multicultural communities and groups from which the club proudly draws its support."
PIF governor Yassir Al-Rumayyan - who has been appointed Newcastle vice-chairman - and part-owners Amanda Staveley and her husband Mehrdad Ghodoussi were present for Sunday's game, which their new side lost 3-2.
Premier League clubs voted on Monday to impose a temporary freeze on any of them signing commercial and sponsorship deals with businesses that have links to their club's owners.
The decision was made at an emergency meeting, after concerns were raised that Newcastle's Saudi Arabian owners could sign lucrative deals with Saudi state-owned companies.
Eighteen clubs voted in favour of the freeze, while Newcastle voted against and Manchester City abstained after their lawyers advised them the vote was unlawful.
The Premier League has declined to comment.
Premier League financial fair play rules allow clubs to make maximum losses of £105m over a rolling three-year period.
Any artificially inflated commercial deals would increase revenues coming into a club and allow them to get around the rules and spend more than they are allowed.
The temporary freeze will be in place for a month while talks are held about a permanent rule change.
One Premier League executive said: "If we didn't have the ban, there would have been nothing to stop Newcastle signing, say, a £100m naming rights deal for their stadium with a Saudi company linked to their owners.
"They could then have used that money to buy players in January and get around our financial fair play rules."